Anchoring device for gantry cranes



0 United States Patent [72] Inventor lhlmunds Anzhs [56] References Cited Eat Ava-dale, Canton, Ohio UNITED STATES PATENTS [21] Appl. No. 781,793 600 757 3/1898 Walsh 212/28 [22] Filed Dec. 6, 1968 3 390 657 7 1968 S h 'de 212 3 4s Patented on. 27, mo c l [73] Assignee Morgan Engineering Primary ExammerHarvey C. Hornsby Mun, n AttorneyBosworth, Sessions, Herrstrom and Cain a corporation of Ohio ABSTRACT: Anchoring devices for securing a travelling shipboard gantry crane to a ships deck and for relieving the gantry legs of the bending moments caused by rolling of the ship. One such anchoring device is located on the ships deck adjacent [54] g gfi g fi g FOR GANTRY CRANES each of the gantry legs and each device includes a rigid anchor tower with means at the top thereof adapted to engage the [52] [1.8. 212/3, crane structure intermediate the ends of the respective gantry 2 12/1 leg .to transmit horizontal loads from the central portion of the [5 1] Int. Cl. 1366c 23/52 gantry leg to the deck through the anchor tower. Means at the [50] Field of Search 212/1, 3, lower portion of the anchor towers engage the bottom of the 144, 28; l04/Consulted; l05/Consulted respective gantry leg.

Patented Oct. 27, 1970 Sheet. Z of 3 llllll llr r-- r 'I ll FIG. I

INVENTOR. RAIMUNDS AUZINS Bowed/t. 5m,

Jmzem ATTORNEYS Patented Oct. 27, 1970 3,536,204

Sheet 2 013 INVENTOR. RAIMUNDS AUZINS /3M, Sm,

J/Mhom 8 6m ATTORNEYS ANCHORING DEVICE FOR GANTRY CRANES CROSS REFERENCE TO RELATED APPLICATIONS This application relates to and incorporates by reference herein the disclosures of copending US. Pat. application Ser. No. 721,821 filed Apr. 16, 1968, now Pat. No. 3,469,716, and US. Pat. No. 3,390,657 of Alfred Schneider.

BACKGROUND OF THE INVENTION This invention relates to traveling gantry cranes and especially those cranes adapted for use on ships designed to carry lighters or containerized cargo for example. More particularly, my invention relates to a system for anchoring the gantry crane such as to a ships deck at a stowage position when the ship is underway.

Such traveling shipboard gantry cranes normally span the cargo holds of the ship and travel on gantry legs along opposite sides of the ships deck between a number of operating positions. For stowage, the crane is moved to a predetermined position along the deck where it must be anchored to the ship securely enough to prevent it from being torn loose or structurally damaged when the ship is operating in heavy seas. Since the crane necessarily has a rather high center of mass relative to the ship, exceptional problems are encountered in designing a satisfactory anchoring mechanism.

A particular problem is that of the bending moments which act on the gantry legs during rolling motion of the ship. Accordingly, it is desirable to secure the crane in such a way that the bending moments acting on the gantry legs during rolling motion of the ship are relieved as much as possible by anchoring structure.

The anchoring mechanism of the present invention satisfies the above requirements and also affords other features and advantages not obtainable from the prior art.

SUMMARY OF THE INVENTION It is among the objects of the invention to anchor a traveling shipboard gantry crane to a ships deck securely enough for operation of the ship in heavy seas..

Another object is to reduce the bending moments acting on the gantry legs of a traveling shipboard gantry crane due to the mass of the crane when it is secured to the deck of the ship and the ship is rolling in heavy seas.

Still another object is to positively restrain longitudinal travel of the crane on the ships deck when the crane is'in an anchored position and the ship is pitching in heavy seas.

These and other objects are accomplished by an anchoring mechanism adapted to engage an outboard anchoring structure on the crane adjacent each gantry leg. Each mechanism includes an anchor tower on the ships deck which is so located as to be adjacent its respective gantry leg when the crane is in its anchoring position. A jack adapted for vertical movement within the anchor tower is provided with a head restrained against lateral movement at the top of the tower and arranged to engage the cranes respective anchoring structure located above when the crane is in its anchoring position. The head takes a lateral shear load when the ship rolls from side to side and thus reduces the moment arm between the top of the gantry leg and the point of application of restraining force.

A pair of horizontal jacks are pivotally connected to the bottom of the anchor tower at horizontallyspaced connection points, each jack being pivotable at one end about a vertical pivot axis through the base. Also, each horizontal jack has a vertical axis, pivotal connector at its opposite end adapted for connection to the respective adjacent gantry leg. When the horizontal jacks are connected to the adjacent gantry leg, they are angularly disposed relative to one another in a horizontal plane and have their included angle intersected by a transverse vertical plane extending laterally of the ship so as to provide a horizontal triangulation efi'ective to positively restrain longitudinal movement of the crane when the ship is pitching in heavy seas as well as a means for applying a lateral restraining force to the bottom of the respective gantry leg.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevation of a traveling gantry crane located on the deck of a ship having anchoring devices embodying the invention, the crane being shown in its stowage position in solid lines and in a'displaced operating position in phantom lines;

FIG. 2 is a fragmentary sectional view on an enlarged scale of one of the anchoring devices, taken on the line 2-2 of FIG.

FIG. 3 is a horizontal section taken on the line 3-3 of FIG.

FIG. 4 is a horizontal section taken on the line 4-4 of FIG. 2; and

FIG. 5 is a horizontalsection taken on the line 5-5 of FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring more particularly to the drawings, there is shown in FIG. 1 a shipboard gantry crane A having four gantry legs B and adapted for travel longitudinally of a ship C with its legs B located on opposite sides of the ships deck. In FIG. 1, the gantry crane A has been moved to a position on the ship C where each of the gantry legs B are located adjacent one of four anchoring devices D mounted on the ships deck on the outboard sides of the gantry legs B. Thus the anchoring devices B serve to anchor the gantry crane A securely to the ships deck during the time that the ship is under way and especially to relieve the bending moments acting on the gantry legs B when the ship C rolls from side to side.

The construction of the gantry crane A and of the ship C, as well as the construction and operation of the traveling gear, hoist mechanism and other associated systems of the crane are described and illustrated in copending US Pat. application Ser. No. 721,82l, filed Apr. 16, 1968 and will not be described in detail herein.

The crane A travels along a pair of spaced rails 10 extending longitudinally of the ship, one rail being on each side of the ships cargo holds. The gantry legs B are supported on wheels 11 carried by trucks 12 which are journaled at the bottom of each leg.

An overhanging structure 13 (FIG. 2) extends beyond the legs B on the outboard side of the crane such as is more completely illustrated in copending U.S. Pat. application Ser. No. 721,821 identified above. The overhanging structure 13 has an anchor receptacle 14 provided adjacent each gantry leg B.

Each device D includes an anchor tower 15 supported on the ship C at the desired stowage location along the deck. The height of the tower above the deck is just slightly less than the vertical spacing of the overhanging structure 13 above the deck as best illustrated in FIG. 2. Accordingly, the gantry crane A can freely pass over the anchor towers 15 during its operating travel.

Located within each anchor tower 15 is a vertical jack unit 16 having a relatively high load rating such as around 125 tons. The jack unit 16 has a threaded shank l7 and a rotatable sleeve 18 threaded on the shank 17 to provide the lifting movement. The sleeve 18 has an axial travel on the threaded shank 17 of about 18 inches and is turned by a fluid motor (not shown) of conventional design. A tubular post 19 is supported at the top of the sleeve 18 in such a way that the sleeve rotation does not turn the post, so that the movement of the post is confined to linear movement within limits of vertical travel.

Located on top of the post 19 is a head 20 with a tapered upper end adapted to engage and mate with the anchor receptacle 14. The head 20 extends through an upper bearing sleeve 21 at the top of the anchor tower 15 which serves to transmit to the tower and thence to the ship's deck, horizontal loads acting on the head 20 caused by pitching and rolling of the ship C. Forming a part of the upper bearing sleeve 21 are a pair of wedge units 22 and 23 spaced approximately from one another and adapted to tightly lock the head 20 in polition in the bearing sleeve once the vertical jack unit 16 has been used to move the head 20 securely into the anchor receptacle 14. The wedge units include wedge blocks 24 and 25 and adjusting bolts 26 and-27."

Spaced below the bearing sleeve 21 is a yoke clamp assembly 28 which guides the vertical movement of the tubular post 19 and restrains lateral movement thereof. The yoke clamp assembly28. includes a fixed portion29 with arms'extending to opposite sides of the anchor tower and a clamping portion 30, each of the portions 29 and 30 having a bearing member in the form of a half ring extending around the tubular post 19. The fixed portion 29 also has an arm 31 welded thereto which extends perpendicularly to the adjacent wall of the anchor tower l5.

Thebottom end of thethreaded shank 17 rests on a resilient preloading pad 32 formed of reinforced rubber wafers in a stack. The preloading pad is retained in a cylindrical receptacle 33.

l A pair of horizontal plates 35 and 36 are located near the base of the anchorgtower 15, the. plates being spaced one above the other to form a fork for mountinga pair of horizontal screw jacks 39 and 40 which can swing in a horizontal plane about spaced vertical axes. The horizontal screw jacks j 39 and 40 are connected by pins to the plates 35 and 36 and e have clevis type eye ends 41 and 42 at their oppositeends which are connectable to a horizontal plate 43 welded to the gantry leg B. The eye ends 41 and 42 are connected to the plate 43 by pins which extend through the eye ends and also through spaced holes in the plate.

. In their connected positions the screw jacks 39 and 40 are located at right angles to one another with their included angle OPERATION The operation of the anchoring device D will be described inches maximum only with respect to the securing of the crane A preparatory to operation of the ship at sea. The releasing'of the craneA and preparation for its operation on the ship merely require the reverse procedure and will be readily apparent following the description of the anchoring operation.

The crane A is initially moved to its anchoring position with 7 each gantry leg B adjacent an anchoring device D. One of the horizontal screw jacks on a leg at each side of the crane, is swiveled so that its clevis end engages the anchoring plate 43 on the respective gantry leg B. The latching pins are-inserted through the clevis ends and the respective hole in the plate 43 and locked with a cotter pin. The respective jacks are then operated to move the crane A to its exact securing position.

At'this time the load frame (not shown) of the gantry crane A is. secured such by lowering it onto a hatch cover and latching it in place. Also the hoist ropes are tightened and all other hoist equipment secured.

When this has been accomplished, all four vertical screw jacks 16 are operated to move the respective heads 20 upward into theirmatching socket 14 in the overhanging structure 13.

Once each head 20 engages its socket 14, the respective jack unit 16 is operated until the preloading pad 32'is depressed-a desired amount. A preloading gauge bar 45, located at the base of the'threaded shank 17, gives a visual indication of the load transmitted through the jack due to the compression of the preloading pad 32. For example, the screw jack may be operated until the bottom of the jack l6 rests on the casing 33 after which the jack may be relaxed until the gauge bar 45 moves up to a predetermined position. Thus, the vertical,

screw jacks 16 do not take up the vertical loads of the gantry legs B but merely exert enough force to keep the heads 20 seated firmly in their respective sockets 14.

The wedge blocks 24 and 25 arethen tightened down using the adjusting bolts 26 and 27 after which the yoke clamp assembly is likewise tightened to secure the tubular ports 19. Finally, the remaining horizontal screw jacks 39 and 40 are connected to their respective plates 43 and tightened down to firmly secure the bottom ends of the gantry legs B to the anchor towers D. L I

With this arrangement, each gantry leg B is secured at two different vertical positions to its respective anchor tower "D and any lateral loads acting on the gantry leg are transmitted to the anchor tower at these two levels. Accordingly when the ship rolls over to one side while at sea and the mass of the gantry crane places a lateral load on the gantry legs, the bendingrnomentacting on the leg is relieved bythe anchor towers D.

For example, referring to FIG. 2 it will be seen that when the shiprolls to the left and the mass of the crane carries a lateral force to the left at the top of the gantry leg, this force could cause a dangerously high bending moment in the gantry leg if the crane were not secured and if the amount of roll were excessive, particularly at the joint between the gantry leg and the transverse girder.

When the crane A is secured to the anchor towers, however, a lateral resisting force to the right (FIG. 2) acts on the gantry leg D intermediate its ends at the level of .the jack head 20. Accordingly,.a lateral resisting force to the left acts on-the bottom of the gantry leg through the respective horizontal screw jacks 39 and 40. The resulting cantileverl' type action on the gantryleg B at the anchor tower D distributes the bending moment acting on the gantry leg over a greater portion of its length and thus reduces the stress at the joint between the top' of the leg and the transverse girder.

It should also be noted that the vertical jacks 16 may be used to jack up the crane for maintenance of the truck, wheels etc.

While the invention has been shown and described with reference to a specific embodiment thereof, this is for the purpose of illustration rather'than limitation and othermodifications and variations will be apparent to those skilled in the art upon a reading of the specification, all within the intended spirit and scope of the invention. Accordingly the patent is not to be limited to the forms specifically illustrated and described nor in any manner that is inconsistent with the extent to which the progress in the art has been advanced by the invention.

" Iclaim:

1. An anchoring device for securing a traveling shipboard gantry crane to a ships deck when the crane is in ananchoring position, the crane having gantry legs which travel along opposite sides of the ships deck and having anchoring structure adjacent each leg intermediate the ends thereof and extending outboard from said leg, comprising an anchor tower secured to said deck adjacent each leg when the crane is inthe anchoring position, vertically movable means secured against lateral movement at the top of said tower and adapted to engage its respective anchoring structure when the crane is in its anchoring position, and being operable to exert a lateral restraining force on said gantry leg when the ship rolls and pitches and a pair of horizontal jacks pivotally connected to said anchor tower at horizontally spaced connection points, each of said horizontal jacks being pivotable at one end about a vertical pivot axis through said base, a vertical axis pivotal connector at the opposite ends of each of said horizontal jacks, said connector being connectable to the bottom end'of the respective adjacent gantry leg to exert a lateral restraining force on said leg when the ship rolls and pitcheswhereby said jacks are angularly disposed with respect to another in a horizontal plane and have their included angle intersected by a transverse vertical plane of said ship to provide a rigid horizontal triangulation.

2. Apparatus as defined inclaim 1 wherein said vertically movable means includes a vertical jack.

3. Apparatus as defined in claim 2 including resilient means operatively associated with said vertical jack for preloading with its respective anchoring structure.

7. Apparatus as defined in claim 6 wherein said clamping means includes adjustable wedge clamps located at the top of said to'wer.

8. Apparatus as defined in claim 6 wherein said clamping means includes adjustable clamps located at vertically spaced locations along said vertically movable means.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Pa S 536 204 Dated October 27 1970 Raimunds Auzins Inventor(s) It is certified that error appears in the aboveidentified patent and that said Letters Patent are hereby corrected as shown below:

Column 4 line 61 "base" should read tower Signed and sealed this 8th day of June 1971.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. WILLIAM E. SCHUYLER, JR. Attesting Officer Commissioner of Patents FORM PC4050 [10-691 USCOMM DC nomad-n9 us. GOVERNMENY "mums orrlce nu o-su-sn 

